Deep-learning-based image super-resolution of an end-expandable optical fiber probe for application in esophageal cancer diagnostics.

Significance: Endoscopic screening for esophageal cancer (EC) may enable early cancer diagnosis and treatment. While optical microendoscopic technology has shown promise in improving specificity, the limited field of view (<1 mm) significantly reduces the ability to survey large areas efficiently in EC screening. Aim: To improve the efficiency of endoscopic screening, we propose a novel concept of end-expandable endoscopic optical fiber probe for larger field of visualization and for the first time evaluate a deep-learning-based image super-resolution (DL-SR) method to overcome the issue of limited sampling capability. Approach: To demonstrate feasibility of the end-expandable optical fiber probe, DL-SR was applied on simulated low-resolution microendoscopic images to generate super-resolved (SR) ones. Varying the degradation model of image data acquisition, we identified the optimal parameters for optical fiber probe prototyping. The proposed screening method was validated with a human pathology reading study. Results: For various degradation parameters considered, the DL-SR method demonstrated different levels of improvement of traditional measures of image quality. The endoscopists' interpretations of the SR images were comparable to those performed on the high-resolution ones. Conclusions: This work suggests avenues for development of DL-SR-enabled sparse image reconstruction to improve high-yield EC screening and similar clinical applications.

Clostridioides difficile infection in cancer patients receiving immune checkpoint inhibitors.

Background: Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, but are associated with immune-mediated diarrhea and colitis (IMDC). Clostridioides difficile infection (CDI) can cause infectious diarrhea with overlapping symptoms. Thus, we sought to elucidate the characteristics of CDI in patients treated with ICI, in the context of IMDC. Methods: We conducted a retrospective, single-center study of adult cancer patients (N=421) with ICI exposure from 2015-2020 and a positive stool nucleic acid amplification test and/or enzyme immunoassay for CDI. Baseline characteristics, treatments, and outcomes were compared between patients with and without concurrent IMDC. Results: Forty-one eligible patients were included, 27 with concurrent IMDC and 14 without. Twenty-seven patients were taking programmed death-1 or its ligand inhibitors and 14 were taking cytotoxic T-lymphocyte-associated antigen 4 inhibitors. Patients with concurrent CDI and IMDC had a longer symptom duration (20 vs. 5 days, P=0.003) and a higher rate of grade 3-4 diarrhea (41% vs. 7%, P=0.033). Among patients with concurrent IMDC, preceding antibiotics (P=0.050) and proton pump inhibitors (PPI) (P=0.038) were used more frequently among individuals who developed CDI after immunosuppressant exposure. Thirty-eight patients received antibiotics for CDI, while 5 required fecal microbiota transplantation for concurrent CDI & IMDC. Conclusions: CDI is common in ICI-treated cancer patients, especially those with IMDC requiring immunosuppressants. Antibiotics did not alter the need for immunosuppressants in those with concurrent IMDC. Use of PPI and antibiotics while receiving immunosuppressants for IMDC was associated with a greater risk of CDI. Further large-scale studies are warranted to clarify the role of CDI, antibiotics and immunosuppression treatment in IMDC patients.

Helping Men Find Their Way: Improving Prostate Cancer Clinic Attendance via Patient Navigation.

Navigation programs aim to help patients overcome barriers to cancer diagnosis and treatment. Missed clinic appointments have undesirable effects on the patient, health system, and society, and treatment delays have been shown to result in inferior surgical cure rates for men with prostate cancer (CaP). We sought to measure the impact of patient navigation on CaP clinic adherence. Patient navigators contacted patients prior to their first encounter for known or suspected CaP between 7/1/2016 and 6/30/2017. Encounters from 7/1/2014 to 6/30/2015 were used as a historical control. Patient-variables were analyzed including age, health insurance status, home address, zip code, race, ethnicity, and referring primary care clinic. Encounter-level variables included diagnosis (categorized as known or suspected CaP), date of appointment, type of appointment [new vs. return], and provider. The associations between several factors including navigation contact and these variables with missed appointment were analyzed using generalized linear mixed effects multivariate logistic regression. A total of 2854 scheduled clinic encounters from 986 unique patients were analyzed. Patient navigation resulted in a lower missed appointment rate (8.8% vs. 13.9%, OR = 0.64, IQR 0.44-0.93, p = 0.02 on multivariable analysis). Lack of health insurance (OR = 13.18 [5.13-33.83]), suspected but not confirmed CaP diagnosis (OR = 7.44 [4.85-11.42]), and Black (1.97 [1.06-3.65]) or Hispanic (OR = 3.61 [1.42-9.16]) race, were associated with missed appointment. Implementation of patient navigation reduced missed appointment rates for CaP related ambulatory encounters. Identifying risk factors for missed appointment may aid in targeting navigation services to those most likely to benefit from this intervention.

Inflammation on Prostate Needle Biopsy is Associated with Lower Prostate Cancer Risk: A Meta-Analysis.

PURPOSE: We performed a comprehensive literature review and meta-analysis to evaluate the association of inflammation on prostate needle biopsies and prostate cancer risk. MATERIALS AND METHODS: We searched Embase®, PubMed® and Web of Science™ from January 1, 1990 to October 1, 2016 for abstracts containing the key words prostate cancer, inflammation and biopsy. Study inclusion criteria were original research, adult human subjects, cohort or case-control study design, histological inflammation on prostate needle biopsy and prostate cancer on histology. Two independent teams reviewed abstracts and extracted data from the selected manuscripts. Combined ORs and 95% CIs of any, acute and chronic inflammation were calculated using the random effects method. RESULTS: Of the 1,030 retrieved abstracts 46 underwent full text review and 25 were included in the final analysis, comprising a total of 20,585 subjects and 6,641 patients with prostate cancer. There was significant heterogeneity among studies (I2 = 84.4%, p <0.001). The presence of any inflammation was significantly associated with a lower prostate cancer risk in 25 studies (OR 0.455, 95% CI 0.337-0.573). There was no evidence of publication bias (p >0.05). When subanalyzed by inflammation type, acute inflammation in 4 studies and chronic inflammation in 15 were each associated with a lower prostate cancer risk (OR 0.681, 95% CI 0.450-0.913 and OR 0.499, 95% CI 0.334-0.665, respectively). CONCLUSIONS: In a meta-analysis of 25 studies inflammation on prostate needle biopsy was associated with a lower prostate cancer risk. Clinically the presence of inflammation on prostate needle biopsy may lower the risk of a subsequent prostate cancer diagnosis.

Magneto-thermally responsive hydrogels for bladder cancer treatment: Therapeutic efficacy and in vivo biodistribution.

Bladder cancer is one of the deadliest forms of cancer in modern medicine which despite recent progress has remained incurable and challenging for researchers. There is unmet need to address this endemic as the number of patients are growing by about 10,000 every year world-wide. Here, we report a minimally invasive magnetic chemotherapy method to address this problem where polyethylene glycol (PEG) functionalized Fe3O4 magnetic nanostructures (MNS) are homogeneously embedded in thermally responsive poly(N-isopropylacrylamide, NIPAAm) hydrogels (HG). The system (HG-MNS) loaded with anti-cancer drug doxorubicin (DOX) incubated with cancer cell lines subjected to external radiofrequency (RF) field can remotely stimulate the release of drug smartly at the site. The in vitro efficacy investigated on bladder cancer (T-24) cell lines showed the potential of the system in dealing with the disease successfully. Further, the materials preferential accumulation via systemic delivery was studied using swiss mice model. Vital tissue organs like liver, lung and heart were analysed by magnetic resonance imaging (MRI). A detail accounts of the materials optimization, cytotoxicity and anti-proliferation activity tests with apoptosis analysis by flow cytometry after RF exposure (250 kHz) to the cells and in vivo biodistribution data are discussed in the paper.

Towards non-invasive diagnostic imaging of early-stage Alzheimer's disease.

One way to image the molecular pathology in Alzheimer's disease is by positron emission tomography using probes that target amyloid fibrils. However, these fibrils are not closely linked to the development of the disease. It is now thought that early-stage biomarkers that instigate memory loss are composed of Aß oligomers. Here, we report a sensitive molecular magnetic resonance imaging contrast probe that is specific for Aß oligomers. We attach oligomer-specific antibodies onto magnetic nanostructures and show that the complex is stable and binds to Aß oligomers on cells and brain tissues to give a magnetic resonance imaging signal. When intranasally administered to an Alzheimer's disease mouse model, the probe readily reached hippocampal Aß oligomers. In isolated samples of human brain tissue, we observed a magnetic resonance imaging signal that distinguished Alzheimer's disease from controls. Such nanostructures that target neurotoxic Aß oligomers are potentially useful for evaluating the efficacy of new drugs and ultimately for early-stage Alzheimer's disease diagnosis and disease management.

Thermoresponsive magnetic hydrogels as theranostic nanoconstructs.

We report the development of thermoresponsive magnetic hydrogels based on poly(N-isopropylacrylamide) encapsulation of Fe3O4 magnetic nanostructures (MNS). In particular, we examined the effects of hydrogels encapsulated with poly-ethylene glycol (PEG) and polyhedral oligomeric silsesquioxane (POSS) surface modified Fe3O4 MNS on magnetic resonance (MR) T2 (transverse spin relaxation) contrast enhancement and associated delivery efficacy of absorbed therapeutic cargo. The microstructural characterization reveal the regular spherical shape and size (∼200 nm) of the hydrogels with elevated hydrophilic to hydrophobic transition temperature (∼40 °C) characterized by LCST (lower critical solution temperature) due to the presence of encapsulated MNS. The hydrogel-MNS (HGMNS) system encapsulated with PEG functionalized Fe3O4 of 12 nm size (HGMNS-PEG-12) exhibited relaxivity rate (r2) of 173 mM(-1) s(-1) compared to 129 mM(-1) s(-1) obtained for hydrogel-MNS system encapsulated with POSS functionalized Fe3O4 (HGMNS-POSS-12) of the same size. Further studies with HGMNS-PEG-12 with absorbed drug doxorubicin (DOX) reveals approximately two-fold enhance in release during 1 h RF (radio-frequency) field exposure followed by 24 h incubation at 37 °C. Quantitatively, it is 2.1 µg mg(-1) (DOX/HGMNS) DOX release with RF exposure while only 0.9 µg mg(-1) release without RF exposure for the same period of incubation. Such enhanced release of therapeutic cargo is attributed to micro-environmental heating in the surroundings of MNS as well as magneto-mechanical vibrations under high frequency RF inside hydrogels. Similarly, RF-induced in vitro localized drug delivery studies with HeLa cell lines for HGMNS-PEG-12 resulted in more than 80% cell death with RF field exposures for 1 h. We therefore believe that magnetic hydrogel system has in vivo theranostic potential given high MR contrast enhancement from encapsulated MNS and RF-induced localized therapeutic delivery in one nanoconstruct.